Electroplating encyclopedia

What effect does copper impurities have on the bath during production using acid zinc plating chemicals?

2022-01-20

    In the production process of using acid zinc plating chemicals, we sometimes find the presence of copper impurities in the acid zinc plating solution. What effect does it have on the plating solution?

    Bigolly Technology made an analysis based on the field experience and the characteristics of the product acid zinc plating chemicals BZ-525,In the acid galvanizing process, the anode hook, hanger and cathode rod are all copper products.If the management is not strict, the copper hook is immersed in the plating solution, and the patina on the cathode rod falls into the galvanizing tank, which will cause the accumulation of copper impurities.In addition, the chemical raw materials used are impure, which is also one of the sources of copper impurities.


    The electrode potential of copper is much more positive than that of zinc, so copper impurities mainly affect the low area of the coating. When the copper impurities in the acid zinc tank reach 0.015g/L, the low area coating will be foggy, and there will be leakage in the low area after light is emitted. When the copper impurity content reaches 0.05g/L, the acid zinc plating solution will become turbid, the entire galvanized layer will become light brown, and the low-level coating will become white and flowery.

    Bigolly Technology has done Hull cell experiment, experimental conditions: 28°C, current 0.5A, time 10min, using acid zinc plating chemicals BZ-525, using brass sheet as cathode.Add an appropriate amount of BZ-525 brightener to the plating solution, and the whole piece is bright; add 0.02g/L copper impurities to the plating solution, the low area of the test piece is a little foggy and yellow, and there is a phenomenon of leakage plating.

    The general method of treating copper impurities in acid zinc plating solution is: add 2g/L zinc powder to the plating solution, stir well for 30 minutes, filter after standing, and then add an appropriate amount of acid zinc plating chemicals, you can plate with good brightness workpiece.

    Therefore, in the production process using acid zinc plating chemicals, we need to regularly deal with copper impurities in the plating solution to reduce the occurrence of failures.If you are interested in acid zinc plating chemicals, please contact Bigolly customer service to get free samples and detailed technical information!

    If you want to know more about copper plating, you can check "Electroplating encyclopedia".